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Related papers: Recent Results on the Anomalous X-ray Pulsars

200 papers

We report the discovery of planetary companions orbiting four low-luminosity giant stars with M$_\star$ between 1.04 and 1.39 M$_\odot$. All four host stars have been independently observed by the EXoPlanets aRound Evolved StarS (EXPRESS)…

Observations using the Rossi X-ray Timing Explorer have discovered dozens of accreting neutron stars with millisecond spin periods in low-mass binary star systems. Eighteen are millisecond X-ray pulsars powered by accretion or nuclear…

Astrophysics · Physics 2009-11-11 Frederick K. Lamb

Influences of the mass, moment of inertia, rotation, absence of stability in the atmosphere and some other parameters of neutron stars on the evolution of pulsars are examined. It is shown that the locations and evolutions of soft gamma…

Astrophysics · Physics 2009-11-10 Oktay H. Guseinov , Askin Ankay , Sevinc O. Tagieva

We search for signatures of planets in 43 intensively monitored microlensing events that were observed between 1995 and 1999. Planets would be expected to cause a short duration (~1 day) deviation on the smooth, symmetric light curve…

A remarkably precise observational relation for pulse core component widths of radio pulsars is used to derive stringent limits on pulsar radii, strongly indicating that pulsars are strange stars rather than neutron stars. This is achieved…

Astrophysics · Physics 2009-10-31 R. C. Kapoor , C. S. Shukre

PSRs J1847-0130 and J1718-37184 have inferred surface dipole magnetic fields greater than those of any other known pulsars and well above the ``quantum critical field'' above which some models predict radio emission should not occur.These…

We have searched for planetary companions around 800 pulsars monitored at the Jodrell Bank Observatory, with both circular and eccentric orbits of periods between $20$ days and $17$ years and inclination-dependent planetary masses from…

Earth and Planetary Astrophysics · Physics 2022-03-14 Iuliana C. Niţu , Michael J. Keith , Ben W. Stappers , Andrew G. Lyne , Mitchell B. Mickaliger

The notable absence of radio pulsars having measured magnetic dipole surface field strengths above $B_0\sim 3\times 10^{13}$ Gauss naturally raises the question of whether this forms an upper limit to pulsar magnetization. Recently there…

Astrophysics · Physics 2009-10-30 Matthew G. Baring , Alice K. Harding

SGRs/AXPs are assumed to be a class of neutron stars (NS) powered by magnetic energy and not by rotation, as normal radio pulsars. However, the recent discovery of radio-pulsed emission in four of this class of sources, where the spin-down…

Solar and Stellar Astrophysics · Physics 2013-04-09 J. G. Coelho , M. Malheiro

We studied spectra for 34 accretion-powered X-ray and one millisecond pulsars that were within the field of view of the INTEGRAL observatory over two years (December 2002 - January 2005) of its in-orbit operation and that were detected by…

Astrophysics · Physics 2007-05-23 E. V. Filippova , S. S. Tsygankov , A. A. Lutovinov , R. A. Sunyaev

Since the true ground state of the hadrons may be strange quark matter (SQM), pulsars may actually be strange stars rather than neutron stars. According to this SQM hypothesis, strange planets can also stably exist. The density of normal…

High Energy Astrophysical Phenomena · Physics 2022-05-30 Abudushataer Kuerban , Jin-Jun Geng , Yong-Feng Huang , Hong-Shi Zong , Hang Gong

We present the results of X-ray and near-IR observations of the anomalous X-ray pulsar 1E 1048.1-5937, believed to be a magnetar. This AXP underwent a period of extreme variability during 2001-2004, but subsequently entered an extended and…

Astrophysics · Physics 2009-06-23 Cindy R. Tam , Fotis P. Gavriil , Rim Dib , Victoria M. Kaspi , Peter M. Woods , Cees Bassa

I present an observational review of the five currently known accretion-driven millisecond X-ray pulsars. A prominent place in this review is given to SAX J1808.4-3658; it was the first such system discovered and currently four outbursts…

Astrophysics · Physics 2009-11-10 Rudy Wijnands

The 6.4 s X-ray pulsar 1E 1048.1-5937 was observed by BeppoSAX in 1997 May. This source belongs to the class of ``anomalous'' pulsars which have pulse periods in range 5-11 s, show no evidence of optical or radio counterparts, and exhibit…

Astrophysics · Physics 2007-05-23 T. Oosterbroek , A. N. Parmar , S. Mereghetti , G. L. Israel

One of the most intriguing properties of the Ap (and Bp) stars is their slow rotation, compared to the superficially normal main-sequence stars in the same temperature range. In recent years, it has emerged that several percent of the Ap…

Solar and Stellar Astrophysics · Physics 2019-12-13 Gautier Mathys

For about half a century the radio pulsar population was observed to spin in the ~0.002-12s range, with different pulsar classes having a spin-period evolution that differs substantially depending on their magnetic fields or past accretion…

High Energy Astrophysical Phenomena · Physics 2022-08-17 Michele Ronchi , Nanda Rea , Vanessa Graber , Natasha Hurley-Walker

Millisecond X-ray pulsars consist of a rapidly-spinning neutron star accreting from a low-mass stellar companion, and are the long-sought evolutionary progenitors of millisecond radio pulsars, as well as promising candidate sources for…

Astrophysics · Physics 2007-05-23 Duncan K Galloway

Rotation-powered millisecond radio pulsars have been spun up to their present spin period by a $10^8$ - $10^9$ yr long X-ray-bright phase of accretion of matter and angular momentum in a low-to-intermediate mass binary system. Recently, the…

High Energy Astrophysical Phenomena · Physics 2015-06-19 A. Papitto , D. F. Torres , N. Rea , T. Tauris

A theoretical investigation of the pulsation behavior of so-named ``anomalous'' Cepheids is presented. The study is based on nonlinear convective pulsation models with $Z$=0.0001 and 0.0004, mass in the range 1.3-2.2 Mo and various…

Astrophysics · Physics 2009-04-13 M. Marconi , G. Fiorentino , F. Caputo

X-ray pulsars (XRPs) are accreting strongly magnetised neutron stars (NSs) in binary systems with, as a rule, massive optical companions. Very reach phenomenology and high observed flux put them into the focus of observational and…

High Energy Astrophysical Phenomena · Physics 2023-04-27 Alexander Mushtukov , Sergey Tsygankov